For a CAM (computer aided manufacturing) apparatus that generates an NC machining program for performing numerical machining of a wire electric discharge machining apparatus, there has been a CAM apparatus implemented with a “cutoff section designating” function for receiving an input for designating a part for cutting off a core. With this function, the CAM apparatus generates a machining program for once stopping machining before machining of a cutoff section and, when an input of machining resumption by an operator is performed, executing cutoff machining. The execution of the machining program is once stopped because, to prevent a core slipped down by the cutoff machining from colliding with a lower guide mechanism of the wire electric discharge machining apparatus, support in a site is necessary for the operator to collect the slipped-off core when the cutoff machining is executed.
On the other hand, as a technology for performing treatment of a core, core fixing machining for depositing an electrode component on the core and fixing the core after cutting to a cut surface is present as a publicly-known technology (see, for example, Patent Literature 1).